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Crossdocks play an important role in supply chain operations. Due to the need to decrease transportation lead time to coordinate with other supply chain activities such as just-in-time, make-to-order, or merge-in-transit strategies, shortening the total transfer time at crossdocks is increasingly important. In this research, we use real-time information about freight transferring within a crossdock to schedule waiting inbound trailers in order to reduce the time freight spends in a crossdock. We use dynamic simulation models to compare the performance of several strategies. These are first-come, first-served, look-ahead, minimum processing time, and minimum total time policies. We examine these under different trailer arrival headways, crossdock layouts, and destination distributions. Our simulation results show that our time-based algorithms save more time than the first-come, first-served and look-ahead policies. In addition, these algorithms appear to result in higher service reliability and productivity. [ABSTRACT FROM AUTHOR]

This article focuses on a study which was conducted to determine the physical distribution productivity measures currently used by major manufacturers, wholesalers and trucking companies in South Carolina. For the purposes of this research, physical distribution activities were limited to transportation and warehousing. It has been estimated that these two functions account for about 75 percent of total physical distribution cost. To fulfill the purpose of this research, two main questions were asked: what measures are routinely used by distribution executives to measure transportation and warehousing productivity and what obstacles are perceived by distribution executives to constrain productivity improvements in transportation and warehousing. Data were collected using a mail survey sent in July 1989. The results indicate that most major South Carolina companies have not progressed much beyond the 1979 national level of sophistication. Less than 20 percent of the South Carolina firms sampled used productivity measures associated with the top two evolutionary stages of productivity measurement. Nearly two-thirds of the sampled companies rely on productivity measures that relate distribution costs to macro outputs such as dollar sales or measures which compare dollar costs to budgeted costs.